1. Field of the Invention
The invention relates to pumps and motors of smallest constructional size, in the following referred to as one of micropump and micromotor. The terms designating orders of magnitude, being of a diameter range below 10 mm, particularly less than 3 mm. Such pumps may find manifold uses in the technical and medical sectors, for instance in microsystems engineering in dosing apparatuses, in medical engineering, as a drive means for one of a micro milling cutter and a bloodstream support pump.
2. Prior Art
Prior art is rich of specifications regarding the principle and the function of gear pumps having an inner wheel and an outer wheel, the wheels being in mating/meshing engagement (compare DE-A 17 03 802, claim 1, page 4, last paragraph and page 6, last paragraph, disclosing radially directed inflow and outflow channels). These operational units to be used as one of pumps and motors are characterized by having two axes, one axis of an inner rotor and another axis of an outer rotor, which axes are offset with respect to each other, and which rotors being in meshing engagement to circumferentially form pressure spaces (pressure chambers) cyclically changing their size and position.